Simple DF Ranch Dressing (otherwise known as 'The Reason My Kids Eat Raw Vegetables')

This recipe was given to me by my friend, Eileen (thanks, Eileen!!!). I keep a container of it in the fridge, alongside containers of cut-up broccoli, thinly sliced carrot sticks & sliced cucumbers. The kids pack their own lunches, and they never "forget" to add vegetables if this dip is on hand.

Combine and whisk:
2 cups mayo (Best foods or Costco's Kirkland Brand)
Juice of 1 large lemon 
6-8 cloves of garlic, pressed through garlic press
4 tablespoons finely chopped onion (I'm pretty generous with the onion & don't measure)
1/2 to 1 teaspoons of salt to taste
pepper to taste (1/2 teaspoon) 
a pinch of cayenne (I've put this in and left it out - kids ate it either way)

You will need to add a bit of liquid at this point to thin it to your desired consistency. Things I've used in the past:
    - squeeze another lemon (or half) into it
    - add some milk, milk alternative or cream, a bit at a time, whisk 
    -  use a food processor to process your onion instead of finely chopping so it releases more juice. A good alternative if your kids won't be receptive to finely chopped onion in the dip.

Eileen's recipe also called for 4 teaspoons dill, but I don't add that because I have two very picky tasters. For them, simpler is better.

You may want to 1/2 this recipe if you have a smaller family.

Can you think of other tasty ways to thin it? Let me know in the comments.